This study quantified the human premature mortality impacts of future ambient air pollution in years 2030, 2050, and 2100, using Representative Concentration Pathway (RCP) emission scenarios. Due to projected reductions in emissions, PM2.5 concentrations were shown to decrease relative to 2000 in all RCP scenarios, and were associated with avoided premature mortality, particularly in 2100. The global mortality burden of ozone markedly increased from 382,000 deaths per year in 2000 to between 1.09 and 2.36 million deaths per year in 2100, across RCPs, mostly due to the effect of increases in population and baseline mortality rates. Trends in future air-pollution related mortality were found to vary regionally across scenarios, reflecting assumptions for economic growth and air pollution control specific to each RCP and region. The authors conclude that the assumed link between economic development and air pollution control in the RCPs requires new and stronger regulations around the world, as well as new control technologies, for the air pollution decreases in the RCPs to be realized.

The authors used modeled ozone and PM2.5 concentrations from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) ensemble, along with projections of future population and baseline mortality rates, to quantify the human premature mortality impacts of future ambient air pollution in years 2030, 2050, and 2100. They — 1) obtained hourly and monthly output data for ozone and PM2.5 from the ACCMIP ensemble simulations for a base year (2000) and for future projections under four Representative Concentration Pathway (RCP) scenarios; 2) applied a health impact function to estimate future air-pollution-related cause specific premature mortality associated with exposure to ozone and PM2.5 ambient air pollution; 3) calculated changes in premature mortality by applying the change in pollutant concentrations in each future year (2030, 2050, and 2100) relative to year 2000 concentrations; 4) gridded country-level population projections for 2030, 2050, and 2100 using ArcGIS 10.2 processing tools; 5) estimated the number of deaths per 5-year age group per country using the country level population; and 6) estimated the global mortality burden of ozone and PM2.5 in 2000 and future periods relative to preindustrial 1850 concentrations.